That was before Stewart and her castmates — including Garrett Hedlund, Kirsten Dunst and Sam Riley — enrolled themselves in a four-week, Beat-style boot camp, studying up on that generation of renegade artists with director Walter Salles ("The Motorcycle Diaries"). The actress recently told us that she learned a ton from those studies ... but that those nerves never went away.

"No, no, they definitely didn't," she confessed.

Yet the entire production — tiny by the standards of the "Twilight" franchise — had a loose, almost impulsive feel to it, and she couldn't have asked for anything more.

"It was everything I wanted it to be," she said. "It exceeded every expectation. It was so much fun. It was wild. We didn't really know what to expect every day."

What KStew dubbed "intimidating visitors" kept popping by the set (writers and biographers who knew guys like Kerouac, Allen Ginsberg and William S. Burroughs), keeping everyone on their toes in terms of historical accuracy and making sure Stewart's anxiety never dissipated.

"There are people that lived that and so we did feel like, 'God, I hope they don't think we're stupid kids doing this movie,' " she laughed. And then there are those obsessive fans of "On the Road," folks who perhaps aren't too different in their fervor than "Twilight" devotees. To those Kerouac fanatics, well, Stewart never knew quite how to react.

"You always question yourself with people like that: 'I love the book. I read it when I was 14. I read it like 15 times. I love it! I love it.' Like, OK!" she laughed, raising a sarcastic thumbs-up.